In common usage today are drawer slides which consist of an outer, an intermediate, and an inner channel having friction reducing ball bearings both between the outer cabinet channel and the intermediate channel as well as between the intermediate channel and the inner drawer channel. Such slides also have ball retainers. These channel slides are particularly durable and are used in situations where the load factor is considerable, such as file cabinets. These channel slides are reliable but are quite costly to manufacture. In addition, they take up a fair amount of space in the cabinet.
Less expensive slides are available and are used in less rigorous applications such as drawers for small tool chests, or other applications. An example of such a slide is shown in U.S. Pat. No. 2,295,697. In this particular type of application an intermediate slide or floating member is constructed from two pieces of stamped metal having out-turned flanges, the two pieces of metal being riveted together. These slides are less expensive but less durable as there is considerable wear because of the metal to metal interface. In addition, the slides are noisy, and not suitable for office or home furniture.
Therefore, there exists a need for a low cost, simplified drawer slide which is capable of long wear and silent operation as well as having considerable load capabilities.
Prior to the development of the new polymeric alloys of plastics and mixtures of plastics, the development of such a slide appeared impossible. The inventor, however, of the present invention, has constructed a one-piece integrally molded elongate plastic intermediate slide which acts as a solid bearing. During experimentation of new slides it was discovered, unknown to the inventor or others, that some of the new space-age plastics such as RYNITE.RTM., which when integrally molded, have surfaces which act as bearing surfaces. When a lubricant is added, a hydro effect is produced and friction between the outer slide, the inner slide, and the intermediate slide is minimized, producing an extremely smooth, quiet, durable drawer slide.
It is therefore an object of the present invention to produce a smooth running, quiet, extremely durable, low friction and low cost drawer slide.